Brushing lacquers



Patented Nov. 20, 1928.

UNITED STATES 1,692,584 PATENT OFFICE.

STANLEY D. SHIPLEY, OF STAMFORD, CONNECTICUT, ASSIGNOR TO ATLAS POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

No Drawing.

This invention relates to nitrocellulose lacquers and lacquer enamels and it hasfor its object to provide an improved substance of this character of such composition that it can be successfully applied with a brush over previously applied coats of paint,. varnish or nitrocellulose lacquer or lacquer enamel, without attacking such previously applied coats.

As far as I am'aware, it has not been possible, rior to this invention, to apply a nitroce lulose lacquer or lacquer enamel upon previously coated surfaces of the character indicated, nor has it been possible to successfully apply such lacquer and lacquer enamel with a brush and get a smooth finish free of brush marks.

The reason that it has not been possible to successfully apply these nitrocellulose lacquers and lacquer enamels with a brush, even upon new surfaces, is that the solvents com- .monly employed, dry or evaporate with such rapidity that pulling develops before the brushing can be completed, with the result that brush marks are left and a smooth surface cannot be secured.

Where an attempt has been made to apply a lacquer or lacquer enamel, consisting of a nitrocellulose base, and the commonly known solvents, upon old work, that is, upon surfaces which have been previously coated with paint, varnish or nitrocellulose lacquer or lacquer enamel, the solvent content of the newly applied coat has attacked and softened the undercoating and it has not been possible to get a good finish. Thisis particularly true if-the application of'the newly applied coat is with a brush, where the mechanical action of the brush tends to dislodge and slough off the softened undercoatings. i 7 To avoid the foregoing .difliculties and t produce a' nitrocellulose lacquer or lacquer enamel which may be successfully applied by brushing, either upon new work or over previously applied coatings, I reduce the amount of active solvent in the lacquer to a quantity just suflicient to keep the nitrocellulosein solution and I employ, in conjunction there with, a substantial proportion of a diluent consisting of a petroleum hydrocarbon, such as gasoline.

Furthermore, I employ a solvent having markedly slower drying qualities than the solvents commonly employed in nitrocellulose lacquers, such as amyl acetate, acetone, butyl acetate, etc. In addition,- the rates of evapo- Application filed September '28, 1925. Serial No. 59,164.

ration of the solvent and the petroleum hydrocarbon diluent employed,,are-such as to insurethe evaporation of the diluent ahead of the complete evaporation of the solvent, since otherwise the nitrocotton would be precipitated from thesolution and the nitrocellulose film would be spoiled. It would be hazy, very weak and probably non-adherent.

By extensive experimentation I have found ethylene glycol mono ethyl ether hereinafter referred to as ethyl glycol, to be particularly adapted for use in the relation set forth, because its rate of evaporation is so, slow that the product may'be applied with a brush and brought to a properly smoothed finish before the drying has proceeded-to such a point as to prevent brushing. Furthermore, the rate of evaporation of the ethyl glycol, with respect to the rate of evaporation of the gasoline. is such as to insure the dissipation of all of the latter ahead of the removal of the former,.so that the possibility of precipitation of the nitrocellulose is eliminated.

mented lacquer) is- Per cent. Ethyl glycol i 40 Gum solution 25- Gasoline L 35 10.0 Nitrocotton 12 oz. per gal. I Titanox 3.25 lbs. per gal.

The gum solution is a six pound cut of gum in toluol.

I The proportion of gasoline and ethyl glycol will vary with the kind and amount of gum solution used, the presence or absence of other nitrocotton solvents, andthe kind and quanof other non-solvents for nitrocotton which may be resent. It is not to understood that the diluent used must consist wholly of asoline or other pgtroleum hydrocarbon. Ot er diluents may present. It is only necessary that a substantial pro ortion of thediluent be=a petroleum hy rocarbon of the nature of gasoline which, experience has shown, has no such destructive efi'ect uppn previously a plied coatings as most of te commonly-use diluents, such as toluol or benzene, for example.

slow drying solvent, I may men-tionas other.

I am aware of the fact that it is common practice to use gasoline as a diluent in nitrocellulose solvent compositions. However, to the best of my knowledge and belief, gasoline has never been designedly employed with a'slow drying solvent to make a. brushing lacquer, nor with a solvent wherein the rates of evaporation of the solvent and diluent were in determined relation, to the end of producing a lacquer which could be applied by brushing and yet give a smooth finish, and which would not attack undercoats, either through the action of the solvent or the action of the diluent.

While I prefer to use ethyl glycol as my practicable slow drying solvents, methyl and ethyl benzoate, methyl salieylate, ethyl lactate, ethyl oxalate, adronal acetate, etc. All

of the above solvents mix well with gasoline.

By a slow drying solvent as defined in the appended-claims, I mean a solvent drying slower than amyl acetate. Since ethyl glycol is a much more active solvent for nitrocellulose than many of the commonly used solclaimis: H

1. A brushing lacquer including a nitrocelvents, such as ethyl, butyl and amyl acetate, for example, a much smaller percentage of ethyl glycol will serve to keep the nitrocellulose insolution and a much greater quantity of diluent, suchas gasoline, may be used.

I Since practically all underooatings contain resins, it follows that diluents which are solvents of resins are destructive of undercoatings. Benzene, toluene, xylene, etc., are much more powerful solvents of practically all of the resins, such as copal, shellac, sandarac,

' demar, kauri, Pontianak,'-etc., than gasoline.

Gasoline has little, if any, solvent efl'ect-upon these resins. f

Having described my invention, what I lulose base, ethyl glycol as a solvent and gaso line as adiluent wherein the gasoline is in such proportions th when he measu- 3. A brushing lacquer consisting in the main of a nitrocellulose base, ethyl glycol as a solvent and: gasoline as a diluent, the pro portions of the ethyl glycol and gasoline being such that the solvent barely maintains the nitrocellulose in solution and does not exercise any appreciable effect upon previously applied undercoatin the gasoline evaporatcipitation of the nitrocellulose is'prevented.

4.. A brushing lacquer comprising a nitroing ahead of the ct yl glycol, whereby pre '16.

cellulose base, a slow drying solvent and gasoline, the proportion of the solvent and gasoline being such that when the lacquer is .exposed to the air by being applied in a brushing coat, the gasoline will be removed by evaporation ahead of the solvent whereby precipitation of the nitrocellulose is prevented.

5. A brushing lacquer consisting in the main of a nitrocellulose base, ethyl glycol as a solvent and gasoline as a. diluent, the gaso line constituting substantially 35% of the liquid content of the lacquer, and the'proportion of gasoline and solvent being such that the solvent barely maintains the nitrocellulose in solution and does not exercise any appreciable softening effect upon previously applied undercoatings, the gasoline evaporating ahead ot the ethyl glycol whereby recipitation of the nitrocellulose is prevented.

6'. A nitrocellulose lhrushing lacquer, consisting of a nitrocotton base, and a liquid ve hicle comprising the following ingredients combined in substantially the proportions stated Ethyl glycol 40 um solution 25 Gasoline", 35

In testimony whereof he afiixes his signature. v STANLEY D. SHIPLEY.

Per cent. 

